Janine Davidson examines the art, politics, and business of American military power.

A suspected al Qaeda militant holds his head as he stands with co-defendants behind bars at the state security court of appeals in Sanaa March 26, 2013. The court on Tuesday upheld jail sentences ranging from four to 10 years against 10 defendants convicted of having links to al Qaeda, the state Saba news agency reported. (Khaled Abdullah/Courtesy Reuters)

The New York Timeshas published letters exchanged in mid-2012 between two senior Al Qaeda leaders, in which Abu Basir of the Arabian Peninsula tries to impart guidance to Abdelmalek Droukdal, leader of Al Qaeda in the Islamic Maghreb (AQIM). Buried in Basir’s letters are a fascinating series of “lessons learned” by the aging terror network. I’ve highlighted four here: